forked from OSchip/llvm-project
149d4d3730
Currently, an invalid asm insn, either in an asm file or
in an inline asm format, might be silently dropped. This patch
fixed two places where this may happen by
signaling the error so user knows what goes wrong.
The following is an example to demonstrate error messages:
-bash-4.2$ cat t.c
int test(void *ctx) {
#if defined(NO_ERROR)
asm volatile("r0 = *(u16 *)skb[%0]" : : "i"(2));
#elif defined(ERROR_1)
asm volatile("r20 = *(u16 *)skb[%0]" : : "i"(2));
#elif defined(ERROR_2)
asm volatile("r0 = *(u16 *)(r1 + ?)" : :);
#endif
return 0;
}
-bash-4.2$ cat run.sh
for macro in NO_ERROR ERROR_1 ERROR_2; do
echo "===== compile for macro" $macro
clang -D${macro} -O2 -target bpf -emit-llvm -S t.c
echo "==llc=="
llc -march=bpf -filetype=obj t.ll
done
-bash-4.2$ ./run.sh
===== compile for macro NO_ERROR
==llc==
===== compile for macro ERROR_1
==llc==
<inline asm>:1:2: error: invalid register/token name
r20 = *(u16 *)skb[2]
^
note: !srcloc = 135
===== compile for macro ERROR_2
==llc==
<inline asm>:1:21: error: unexpected token
r0 = *(u16 *)(r1 + ?)
^
note: !srcloc = 210
-bash-4.2$
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 329849
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|---|---|---|
| .. | ||
| BPFAsmParser.cpp | ||
| CMakeLists.txt | ||
| LLVMBuild.txt | ||